Post on 07-Apr-2020
H15161.3
Technical White Paper
Dell EMC Unity: Performance Metrics
Abstract This document explains the performance metrics features for Dell EMC Unity
systems including viewing performance information, creating charts, and
downloading performance archive files.
October 2019
Revisions
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Revisions
Date Description
October 2019 Template and format update
The information in this publication is provided “as is.” Dell Inc. makes no representations or warranties of any kind with respect to the information in this
publication, and specifically disclaims implied warranties of merchantability or fitness for a particular purpose.
Use, copying, and distribution of any software described in this publication requires an applicable software license.
Copyright © 2017-2019 Dell Inc. or its subsidiaries. All Rights Reserved. Dell, EMC, Dell EMC and other trademarks are trademarks of Dell Inc. or its
subsidiaries. Other trademarks may be trademarks of their respective owners. [10/14/2019] [Technical White Paper] [H15161.3]
Table of contents
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Table of contents
Revisions............................................................................................................................................................................. 2
Table of contents ................................................................................................................................................................ 3
Executive summary ............................................................................................................................................................. 4
Audience ............................................................................................................................................................................. 4
Terminology ........................................................................................................................................................................ 4
1 Performance metrics .................................................................................................................................................... 6
1.1 Performance metrics database ........................................................................................................................... 6
1.2 Performance metrics aging policy ...................................................................................................................... 6
1.3 Unisphere performance metrics page ................................................................................................................ 6
1.3.1 Overview ............................................................................................................................................................. 6
1.3.2 Add charts ........................................................................................................................................................... 8
1.3.3 Viewing metrics................................................................................................................................................... 9
1.3.4 Viewing range and charts refresh ..................................................................................................................... 10
1.3.5 Breakdown categories and filter options .......................................................................................................... 12
1.3.6 Click data point to view contributors ................................................................................................................. 14
1.3.7 Export option ..................................................................................................................................................... 14
1.4 Download performance archive files ................................................................................................................ 15
1.5 Unisphere CLI performance metrics ................................................................................................................. 17
1.5.1 Performance metrics service ............................................................................................................................ 17
1.5.2 Available performance metrics ......................................................................................................................... 18
1.5.3 Historical performance metrics ......................................................................................................................... 18
1.5.4 Real-time performance metrics ........................................................................................................................ 19
1.6 REST API performance metrics ....................................................................................................................... 20
2 Troubleshooting techniques ....................................................................................................................................... 22
2.1 Performance categories ................................................................................................................................... 22
2.2 Triage general workflow ................................................................................................................................... 22
3 Conclusion .................................................................................................................................................................. 25
A Unisphere performance metrics ................................................................................................................................. 26
A.1 Historical performance metrics ......................................................................................................................... 26
A.2 Real-time performance metrics ........................................................................................................................ 33
B Technical support and resources ............................................................................................................................... 37
B.1 Related resources............................................................................................................................................. 37
Executive summary
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Executive summary
Data is a crucial part of the day-to-day operations of an organization. Data access, data availability, system
performance, and capacity are always top concerns of storage administrators. Advanced data services like
thin provisioning, replication, and snapshots provide important benefits but also add complexity to storage
environments. Addressing this complexity requires a wide range of understandable and differentiating
performance metrics to diagnose and troubleshoot issues or accomplish routine maintenance operations.
Dell EMC™ Unity storage systems address these concerns by providing capacity and performance metrics
through simple-to-use management interfaces including Dell EMC Unisphere™, the Unisphere CLI (UEMCLI),
and the built-in RESTful API. This expansive set of information enables storage administrators to easily
analyze system performance on demand while monitoring capacity details, ensuring users are always able to
access their critical data.
This white paper discusses the performance metrics available on Dell EMC Unity storage systems and
describes how to view and gather performance metrics data from the storage system. The paper also
describes different functionality related to performance metrics and provides guidelines for using these
features. This paper does not address off-array monitoring options. For more information, see the Unisphere
Online Help, Unisphere CLI documentation, and Dell EMC Unity REST API documentation.
Audience
This white paper is intended for Dell EMC customers, partners, and employees considering using capacity
and performance metrics for Dell EMC Unity storage systems. It is assumed that the reader is at least an IT
generalist who has experience as a system or network administrator.
Terminology
Bandwidth: Maximum amount of data that can be transmitted through a data channel per unit of time.
Commonly expressed in megabytes per second (MB/s).
CIFS: Common Internet File System. See Server Message Block (SMB).
Fibre Channel (FC): A high-speed networking technology that is used to transport Small Computer Systems
Interface (SCSI) commands over a Fibre Channel fabric.
Internet SCSI (iSCSI): A protocol that provides a mechanism for accessing raw block-level data storage over
network connections. The iSCSI protocol is based on the network-standard client/server model with iSCSI
initiators (hosts) acting as storage clients and iSCSI targets acting as storage interfaces. Once a connection is
established between an iSCSI host and the iSCSI interface, the host requests storage resources and services
from the interface.
IOPS: Input/output operations per second.
NAS server: A file storage server that uses SMB or NFS protocols to catalog, organize, and transfer files
within designated file system shares. A NAS Server must be created before creating file-level storage
resources such as SMB or NFS file systems, or VMware® NFS datastores.
Network File System (NFS): An access protocol that enables users to access files and folders from
Linux/UNIX hosts located on a network.
Terminology
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Pool: A collection of drives configured with a particular storage profile. The storage profile defines the type of
drives used to provide storage and the type of RAID configured on the drives. The storage pool’s
configuration defines the number of drives and quantity of storage associated with the pool.
REST API: An application programming interface that utilizes familiar HTTP operations like GET, POST, and
DELETE. REST architecture includes certain constraints that ensure that different implementations of REST
conform to the same guiding principles, thereby allowing developers the ease of application development
when working with different REST API deployments.
Server Message Block (SMB): A file sharing protocol that allows users to share files systems over the
Internet and intranets. This is typically used in Windows environments. Also known as Common Internet File
System (CIFS), Microsoft’s implementation of SMB.
Storage processor: A hardware component that performs Dell EMC Unity storage operations such as
creating, managing, and monitoring storage resources.
Unisphere: The web-based user interface for managing Dell EMC Unity storage systems.
Unisphere CLI (UEMCLI): The command-line interface for managing Dell EMC Unity storage systems.
Performance metrics
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1 Performance metrics Dell EMC Unity storage systems provide the ability to view performance metrics from the system level to the
individual drives. The performance metrics are located in the Unisphere Performance page. Performance data
can be used to diagnose and troubleshoot issues within a storage environment.
1.1 Performance metrics database Performance metrics data is located in a database stored on the first four system drives. This performance
database space is fixed at 16 GB in size and is automatically reserved on every storage system. The fixed
size allows the system to retain historical metrics for a fixed duration of time, although not indefinitely (see
section 1.2).
The target for total consumed space for storing metrics is 70% of the available 16 GB reserved system space
for metrics. If there is a lack of space, the system decreases the retention period for the oldest metrics while
attempting to retain at least 24 hours’ worth of data for all collected metrics.
1.2 Performance metrics aging policy Performance metrics data is consolidated and averaged depending on the age of the data so that the metrics
database can hold older data for longer periods. For example, data that is greater than 3 days old is
consolidated from 1 minute intervals to 5 minute intervals for a longer sampling interval. The same concept is
applied at 14 days and 28 days, respectively. Table 1 shows the full list of metric retention periods and
associated sampling intervals.
Sampling intervals and retention periods
Sampling interval
Retention period
1 minute 3 days
5 minutes 14 days
1 hour 28 days
4 hours 90 days
1.3 Unisphere performance metrics page On Dell EMC Unity systems, there are several ways to view metrics data that have been collected by the
system. This includes viewing metrics from the Unisphere Performance Page, from the Unisphere CLI, and
from the Dell EMC Unity RESTful API.
1.3.1 Overview As shown in Figure 1, to open the Performance Page in Unisphere, click Performance in the left-hand
navigation menu under the SYSTEM category. This page shown in Figure 2 allows viewing and modifying the
metrics charts shown on that dashboard as well as adding additional dashboards to adjust the views to
specific needs. The charts themselves are interactive, allowing modifying the time view range or hovering
over the charts to see individual metric points and comparing with other charts on the page for
troubleshooting purposes. Leveraging these capabilities enables quickly locating any high-level performance
issues as well as drilling down further for more details by utilizing various breakdown categories and filter
Performance metrics
7 Dell EMC Unity: Performance Metrics | H15161.3
options on each chart. The filter options chosen on one chart do not affect any other charts on the dashboard.
By default, the Historical Charts dashboard page is populated with performance charts which show the
system’s CPU Utilization, File System Bandwidth, LUN IOPS, LUN Bandwidth, and File System IOPS. This
page displays data collected within a preset or customized time range.
Dell EMC Unity OE version 4.1 added the Real-time Charts dashboard. When viewing metrics in the real-time
dashboards, new data points are automatically added every 5 seconds. The Real-time Charts dashboards
display data collected during the current session, over a maximum time range of 15 minutes. The session
ends when navigating away from the current tab and restarts when navigating back to the tab. A dashboard
can display up to four real-time metrics charts at a time.
For a full list of available metrics in the Unisphere GUI including descriptions, see appendix A.
Performance page (navigation menu)
Performance metrics
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Performance page in Unisphere
1.3.2 Add charts While in the Performance page, to add a chart to a dashboard, select the dashboard’s name and click Add
Charts. The available charts that can be added to the dashboard are shown. The Add Historical/Real-Time
Charts menu (Figure 3), separates charts into categories like system-level or resource-level, allowing for easy
searches of related metrics.
Dashboard actions and Add Charts menu
Performance metrics
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1.3.3 Viewing metrics When viewing metrics on the Performance page of Unisphere, hover the mouse over individual charts to see
specific graphed metric values along with associated timestamps. Hovering over one chart automatically
shows metric values in all other visible charts on the page for the same timestamp as seen in Figure 4. This
allows for fast comparison between metric charts when conducting troubleshooting steps.
Metric charts (hover)
For more customized viewing, move charts to different parts of the dashboard. Hover the cursor over the top
part of a chart (the cursor changes to a movement cursor as shown in Figure 5), drag to move the chart to a
new location on the page.
Relocating metric charts (cursor highlighted)
Performance metrics
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The Performance page also supports expanding metric charts for easier viewing. Hover over a chart and drag
the bottom-right corner of the chart to the right of the page (see Figure 6). The chart must be on the left side
of the page to be expanded to the right.
Expanding charts (chart expansion corner highlighted)
1.3.4 Viewing range and charts refresh To change the viewing time range of the metric charts displayed on the dashboard, use either the default time
ranges (shown in Table 2) or use a custom time range as shown in Figure 7. The different time ranges
correlate to specific sampling intervals, as shown in Table 2.
Time ranges and associated sampling intervals
Time range setting
Sampling interval
Last 1 Hour 1 minute
Last 4 Hours 1 minute
Last 12 Hours 5 minutes
Last 24 Hours 5 minutes
Last 7 Days 1 hour
Last 30 Days 4 hours
Last 90 Days 4 hours
Custom Varies based on the length of the range. If the range is more than one week, the sampling interval is 4 hours.
Performance metrics
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The center of Figure 7 shows how the date and times for the start and end points of the viewing window
correlate to the metric points shown in the charts. To view the latest metrics, select the Auto Refresh
checkbox to the right of the time window. To change the viewing window itself, use the arrows to adjust the
time or zoom into a specific range as shown in Figure 8.
Navigator bar, default time ranges, and Auto Refresh
Zooming the chart view
Performance metrics
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1.3.5 Breakdown categories and filter options At the top of each metric chart there are different checkbox buttons (breakdown categories). When selected,
the chart updates according to the breakdown category with separate lines designating each component of
the breakdown. For example, Figure 9 shows the LUN IOPS metric chart with the Storage Processor
breakdown category selected allowing for SP A, SP B, and average metrics to be graphed on separate lines.
Click the LEGEND in each chart to see the labels for each graphed line.
LUN IOPS metric chart (breakdown)
To hide certain lines from being graphed, add a filter by clicking the check box next to the line labels in the
legend, as seen in Figure 10. This helps isolate metrics for further investigation.
LUN IOPS metric chart (filtered)
Performance metrics
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With the Unity OE 4.5 release, for object-level line charts such as those for LUNS, file systems, drives, and so
forth, select Percentage View to view data points as percentage values instead of absolute values.
Percentage View option
The Percentage View breakdown shows each resource’s contribution as a percentage of the total. This option
is only available in Unisphere and is available for both historical and real-time charts. It is deselected by
default and only available when all other breakdown options are deselected.
Percentage view example
Performance metrics
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1.3.6 Click data point to view contributors To view more details, click a data point tooltip in a chart that has the message Click on a data point to view
contributors. Click the data point with this message to open the Top 20 Contributors tooltip shown in Figure
13. In the tooltip, use the Choose Group drop-down menu to view the line chart for the option selected. The
options listed in the drop-down menu vary depending on the Breakdown By field chosen. To compare the
metrics, select the resources and click the Generate Chart button, which generates a chart with the metrics
for the resources selected.
Top 20 contributors for a data point
1.3.7 Export option To export metrics data into a comma separated value (CSV) format, hover over a metric chart and click the
Export button as shown in Figure 14. This action downloads the metrics into a CSV file with data of the
current view shown in the graph including any applied breakdown categories and filter options. Make sure to
adjust the chart to show the desired information before clicking the Export button.
Export metrics button
Performance metrics
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With Dell EMC Unity OE version 4.2, the Historical Charts dashboards allow exporting data of all the
displayed charts to a single CSV file. In the Performance page, to export all the data, select the dashboard’s
name and click Export Chart Data, as shown in Figure 15.
Export chart data
1.4 Download performance archive files Dell EMC Unity OE version 4.2 introduced an option to download performance archive files from Unisphere,
UEMCLI, and REST API. Performance archive files are similar to performance historical metrics, except the
archive collects raw data at a predefined interval (10 seconds), and the data are not averaged into larger
intervals. The system generates a performance archive file for every hour and assures there are performance
archives for at least the last 48 hours. Download and send performance archive files to Dell EMC Support to
troubleshoot performance issues.
To download a performance archive file from Unisphere, navigate to the Downloads page shown in Figure
16. Individual archive files or all files within a specific time range are downloadable. The Select specific
archive files option shown in Figure 17 allows selecting individual archive files from the list. With the Select
files within a specific time range option (Figure 18), click the calendar icon to select a custom date and time
range.
Performance metrics
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To obtain a record of performance for an extended period of time, is recommended to download the
performance archive files from the system for the desired period. For example, if one weeks’ worth of data is
needed, download the performance archive files for each day of the week.
Service > Downloads > Performance Archive File page
The Size column for a Performance Archive File table gives the size of the archive file in the system. When
clicking the Download button, the file(s) is (are) compressed into a zip file of smaller size.
Selecting specific archive files
Performance metrics
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The Total number of selected archive files field states the number of files that are selected or are within the
time range selected. The Total size of selected archive files give the size of the file(s) selected. Both fields
update accordingly by selection.
Selecting archive files within a specific time range
1.5 Unisphere CLI performance metrics Unisphere CLI allows running commands to a Dell EMC Unity system through a command prompt on a
several host types including Microsoft® Windows® and Unix/Linux® hosts. The Unisphere CLI is intended to be
used by advanced users who would like to use command prompts to script complex or routine tasks. The
same actions performed in the Unisphere GUI can also be completed through the Unisphere CLI. In terms of
performance metrics, use the Unisphere CLI to enable or disable the metrics collection service, view available
metrics paths, and view historical or real-time metric values. The metrics collection service is enabled by
default.
For more information on using Unisphere CLI and its related syntax, see the Dell EMC Unity Family
Unisphere CLI User Guide on Dell EMC Support.
1.5.1 Performance metrics service Using the Unisphere CLI, enable or disable the metrics collection service on the Dell EMC Unity system by
using the /metrics/service CLI command path. When viewing the current status of the metrics collection
service, the system displays the current metrics data aging retention policy values as shown in Figure 19.
Even if the metrics collection service is disabled, the 16 GB of reserved metrics space is still reserved by the
system.
Unisphere CLI metrics service command
Performance metrics
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1.5.2 Available performance metrics The Unisphere CLI allows using the /metrics/metric command path to see all available metrics paths (both
historical and real-time). A metrics path must be specified when viewing metrics using Unisphere CLI. An
example of the output running the /metrics/metric command is shown in Figure 20.
Unisphere CLI available metrics paths command
1.5.3 Historical performance metrics Unisphere CLI allows viewing historical performance metrics of the Dell EMC Unity system in predefined
intervals. To view all available historical metrics paths, use the same /metrics/metric command path as
previous, but with the added –availability historical option as shown in Figure 21.
Unisphere CLI available historical metrics available paths command
To use a specific historical metrics path to view corresponding metric values, use the /metrics/value/hist
command path in the Unisphere CLI. This command requires specifying the time interval of the data to be
viewed by using the –interval option. The predefined interval values are 60 (1 minute), 300 (5 minutes), 3600
Performance metrics
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(1 hour), and 14400 seconds (4 hours). To specify the start and end times of the desired metrics time period,
add the –from and –to options (see an example in Figure 22).
Unisphere CLI Historical Metrics
1.5.4 Real-time performance metrics All available metrics in the /metrics/metric path command can be used to view real-time metrics on Dell EMC
Unity systems. Real-time metrics can be viewed using the /metrics/value/rt command and using the –path
option to specify a specific metric path to view metric values for. This also requires specifying the interval
using the –interval option and providing an acceptable value (5 to 300 seconds). See Figure 23 for an
example.
Unisphere CLI real-time metrics
Performance metrics
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1.6 REST API performance metrics The REST API can be used to collect performance metrics from Dell EMC Unity systems. To view all
available performance metrics, run the GET /api/types/metric/instances REST API command. An example
of the command being run is shown in Figure 24. Additional information can be added to the query to find out
if a metric path is available for historical or real-time metrics by adding isHistoricalAvailable or
isRealTimeAvailable as additional fields to display.
Available Metrics Paths through REST API
Once a specific path is found, use the name of the path to query metrics from REST API by using the GET
/api/types/metricValue/instances for historical metrics or the POST
/api/types/metricRealTimeQuery/instances command for real-time metrics. An example of a historical
metric query is shown in Figure 25 with the metric path of sp.*.cpu.summary.utilization.
Historical metrics query
Performance metrics
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For real-time metrics, a query first needs to be initiated as seen in Figure 26 with the path
sp.*.cpu.summary.busyTicks. The system replies with a query ID which can be used to gather results with
the GET /api/types/metricQueryResult/instances?queryId EQ <#> command path as seen in Figure 27.
Real-time metrics query
Metric query result (real-time metrics)
For additional information on using REST API and associated syntax, see the Dell EMC Unity Family
Unisphere Management REST API Reference Guide and the Dell EMC Unity Family Unisphere Management
REST API Programmer’s Guide on Dell EMC Support.
Troubleshooting techniques
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2 Troubleshooting techniques
2.1 Performance categories When viewing historical metrics on Dell EMC Unity systems, there are several performance metrics available
that are separated into several high-level performance categories. Table 3 explains the meaning of each
category to clarify which charts to view when troubleshooting system(s).
Performance categories (Unisphere GUI)
Performance category Description
System-Cache Provides a high-level view of the cache friendliness of the workload.
System-IO Provides a system-level aggregation of front-end (client-to-system) activity.
System-Resources Provides a system-level aggregation of hardware activity (CPU, drives, ports).
LUN Provides a detailed breakdown of client block activity on a per-LUN basis.
File System Provides a detailed breakdown of client file activity on a per-FS basis.
vVol Datastore Provides a detailed breakdown of VMware vSphere® Virtual Volumes™ (vVols) datastore activity on a per-vVol basis.
Fibre Channel Port Provides a detailed breakdown of client block activity on a per-port basis (for FC).
iSCSI Interface Provides a detailed breakdown of client block activity on a per-port basis (for iSCSI).
Ethernet Port Provides a detailed breakdown of client block/file activity on a per-port basis.
Drive Provides a detailed breakdown of drive activity on a per-drive basis.
Tenant Provides a detailed breakdown of tenant activity on a per-tenant basis.
2.2 Triage general workflow Use the available performance metrics on Dell EMC Unity systems to complete performance troubleshooting
on the system, determining potential bottlenecks or issues within the storage environment. When conducting
performance troubleshooting, it is useful to know which metrics charts provide the necessary information to
help drill down to the root cause of the issue. For a broad example, assume that an application running on a
Dell EMC Unity storage system is reported to be experiencing slow response times, and client, server, and
network issues have been determined to not be the cause of the issue. In this case, initiate performance
troubleshooting in the storage environment to resolve the slow response times.
Troubleshooting techniques
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The following is a general workflow for performance troubleshooting on Dell EMC Unity systems.
1. Starting at a system level, investigate aggregated system statistics.
a. Look at System-IO metric charts and find where the bulk of client workload is originating, such as
the LUN or FS (SMB, NFS).
b. Look at System-Resources metric charts and determine if hardware usage aligns with incoming
client workload, and also see if CPU Utilization may be an issue.
2. Drill-down to potential hardware bottlenecks.
a. If affected workload is from a LUN (through FC), go to the Fibre Channel Port metric charts to see
if the load is distributed evenly among configured ports or if any ports are too heavily utilized.
b. If affected workload is from a LUN (through iSCSI), go to the iSCSI Interface metric charts to see
if the load is distributed evenly among configured ports or if any ports are too heavily utilized.
c. If affected workload is from a file system, go to the Ethernet Port metric charts to see if the load is
distributed evenly among configured ports or if any ports are too heavily utilized.
3. If load on ports is determined not be the issue, investigate physical drives.
a. Track the busiest system resources (LUN, FS, datastore) back to the physical drives which
comprise the corresponding storage pool.
i. Go to Drive metric charts and select the appropriate drives to see if they are causing the
bottleneck. The drives can be sorted by Pool as shown in the following screen.
Troubleshooting techniques
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The above steps are complemented by using the Dell EMC Unity Best Practices Guide when configuring
system settings and system resources, including recommendations on system utilization and workloads. The
guide also includes recommended maximum limits for hardware resources. Find the Dell EMC Unity: Best
Practices Guide on Dell EMC Support.
Conclusion
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3 Conclusion By leveraging performance metrics functionality on Dell EMC Unity systems, administrators have the ability to
view, monitor, and analyze metrics data with the Unisphere graphical interface, the Unisphere CLI, or the
REST API. Administrators with different backgrounds and knowledge can gather information from Dell EMC
Unity storage systems in the method that is most familiar to them. Whether users are diagnosing current
issues or planning for future initiatives, the available metrics functionality provides administrators the ability to
make well-informed decisions for their storage environments.
Unisphere performance metrics
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A Unisphere performance metrics
The following tables outline the various performance metrics available in Unisphere. The tables are organized
by breakdown category, and include each performance metric and a brief description. For more information
on each performance metric, refer to Unisphere Online Help on the Dell EMC Unity system or on Dell EMC
Support.
A.1 Historical performance metrics
System-cache performance metrics
Metric Name Description Additional breakdown categories
Cache Dirty Size Total amount of data in the write cache, in MB, that has not yet been flushed out to drives.
Storage Processor
Cache Read Hit IOPS1 Total number of read I/O requests, in I/O per second that do not demand a new allocation of cache memory.
Storage Processor
Cache Read Miss IOPS1
Total number of read I/O requests, in I/O per second, passing through, that is, not served by cache.
Storage Processor
Cache Write Hit IOPS1 Total number of write I/O requests, in I/O per second that do not demand a new allocation of cache memory.
Storage Processor
Cache Write Miss IOPS1
Total number of write I/O requests, in I/O per second, passing through, that is, not served by cache.
Storage Processor
FAST Cache Dirty Ratio Ratio of dirty pages to total pages in the FAST Cache, expressed as a percent.
Storage Processor
1 If FAST Cache is configured, this metric includes I/O requests passing through the FAST Cache.
System-IO performance metrics
Metric name Description Additional breakdown categories
CIFS Bandwidth Total amount of CIFS (SMB) I/O requests, in KB/s, across all ports in the storage system.
Storage Processor
Read/Write
CIFS I/O Size Average size of CIFS (SMB) I/O requests, in KB, across all ports in the storage system. Calculated as a weighted average, which gives more weight to the SP with the highest number of CIFS I/O requests.
Storage Processor
Read/Write
CIFS IOPS Total number of CIFS (SMB) I/O requests, in I/O per second, across all ports in the storage system.
Storage Processor
Read/Write
Unisphere performance metrics
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Metric name Description Additional breakdown categories
CIFS Response Time Average time spent completing CIFS I/O requests, in microseconds, across all file systems in the storage system. Calculated as a weighted average, which gives more weight to the file systems with the highest number of I/O requests.
Storage Processor
Read/Write
Client File System Bandwidth
Total amount of file system client I/O requests, in KB/s, across all file systems in the storage system.
Storage Processor
Read/Write
Client File System I/O Size
Average size of file system client I/O requests, in KB, across all file systems in the storage system.
Storage Processor
Read/Write
Client File System IOPS Total number of file system client I/O requests, in I/O per second, across all file systems in the storage system.
Storage Processor
Read/Write
Client File System Response Time
Average time spent completing file system client I/O requests, in microseconds, across file systems in the storage system.
Storage Processor
Read/Write
File System Bandwidth Total amount of file system I/O requests, in KB/s, across all file systems in the storage system.
Storage Processor
Read/Write
File System I/O Size Average size of file system I/O requests, in KB, across all file systems in the storage system. Calculated as a weighted average, which gives more weight to the file systems with the highest number of I/O requests.
Storage Processor
Read/Write
File System IOPS Total number of file system I/O requests, in I/O per second, across all file systems in the storage system.
Storage Processor
Read/Write
LUN Bandwidth Total amount of LUN I/O requests, in KB/s, across all LUNs in the storage system.
Storage Processor
Read/Write
LUN I/O Size Average size of LUN I/O requests, in KB, across all LUNs in the storage system. Calculated as a weighted average, which gives more weight to the LUNs with the highest number of I/O requests.
Storage Processor
Read/Write
LUN IOPS Total amount of LUN I/O requests, in I/O per second, across all LUNs in the storage system.
Storage Processor
Read/Write
LUN Queue Length Average number of LUN I/O requests in the system queue, in counts per second, across all LUNs in the storage system. Calculated as a weighted average, which gives more weight to the LUNs with the highest number of I/O requests.
Storage Processor
Read/Write
Unisphere performance metrics
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Metric name Description Additional breakdown categories
LUN Response Time Average time spent completing LUN I/O requests, in microseconds, across all LUNs in the storage system. Calculated as a weighted average, which gives more weight to the LUNs with the highest number of I/O requests.
Storage Processor
NFS Bandwidth Total amount of NFS I/O requests, in KB/s, across all ports in the storage system.
Storage Processor
Read/Write
NFS I/O Size Average size of NFS I/O requests, in KB, across all ports in the storage system. Calculated as a weighted average, which gives more weight to the SP with the highest number of NFS I/O requests.
Storage Processor
Read/Write
NFS IOPS Total number of NFS I/O requests, in I/O per second, across all ports in the storage system.
Storage Processor
Read/Write
NFS Response Time Average time spent completing NFS I/O requests, in microseconds, across all file systems in the storage system. Calculated as a weighted average, which gives more weight to the LUNs with the highest number of I/O requests.
Storage Processor
Read/Write
vVol Datastore Bandwidth
Total amount of vVol I/O requests, in KB/s, across all vVols in the storage system.
Storage Processor
Read/Write
vVol Datastore IOPS Total number of vVol I/O requests, in I/O per second, across all vVols in the storage system.
Storage Processor
Read/Write
vVol Datastore Response Time
Average time spent completing vVol I/O requests, in microseconds, across all vVols in the storage system. Calculated as a weighted average, which gives more weight to the vVols with the highest number of I/O requests.
Storage Processor
Unisphere performance metrics
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System resources performance metrics
Metric name Description Additional breakdown categories
CPU Utilization Total amount of processing cycles, as a percentage, across all cores in the storage system SPs.
Storage Processor
Drive Bandwidth Total amount of drive I/O requests, in KB/s, across all drives in the storage system used in provisioned storage.
Storage Processor
Read/Write
Drive IOPS Total number of drive I/O requests, in I/O per second, across all drives in the storage system used in provisioned storage.
Storage Processor
Read/Write
Ethernet Bandwidth Total amount of Ethernet I/O requests, in KB/s, across all non-management Ethernet ports in the storage system.
Storage Processor
Read/Write
Ethernet Packets Total amount of Ethernet I/O requests, in I/O per second, across all non-management Ethernet ports in the storage system.
Storage Processor
Read/Write
Fibre Channel Bandwidth
Total amount of Fibre Channel I/O requests, in KB/s, across all ports in the storage system.
Storage Processor
Read/Write
Fibre Channel IOPS Total number of Fibre Channel I/O requests, in I/O per second, across all ports in the storage system.
Storage Processor
Read/Write
iSCSI Bandwidth Total amount of iSCSI I/O requests, in KB/s, across all ports in the storage system.
Storage Processor
Read/Write
iSCSI IOPS Total number of iSCSI I/O requests, in I/O per second, across all ports in the storage system.
Storage Processor
Read/Write
Unisphere performance metrics
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LUN performance metrics
Metric name Description Additional breakdown categories
Bandwidth Total amount of LUN I/O requests, in KB/s, for the selected LUN or LUNs.
Storage Processor Read/Write
I/O Size Average size of LUN I/O requests, in KB/s, for the selected LUN or LUNs.
Storage Processor Read/Write
IOPS Total amount of LUN I/O requests, in I/O per second, for the selected LUN or LUNs.
Storage Processor Read/Write
Queue Length Average number of LUN I/O requests in the system queue, in counts per second, for the selected LUN or LUNs.
Storage Processor Read/Write
Response Time Average time spent completing LUN I/O requests, in microseconds, for the selected LUNs in the storage system. Calculated as a weighted average, which gives more weight to the LUNs with the highest number of I/O requests.
Storage Processor
File system performance metrics
Metric name Description Additional breakdown categories
Bandwidth Total amount of file system I/O requests, in KB/s, for the selected file system or file systems.
Storage Processor Read/Write
Client Bandwidth Total amount of file system client I/O requests, in KB/s, for the selected file systems.
Read/Write
Client I/O Size Average size of file system client I/O requests, in KB, for the selected file systems.
Read/Write
Client IOPS Total number of file system client I/O requests, in I/O per second, for the selected file systems.
Read/Write
Client Response Time Average time spent completing file system client I/O requests, in microseconds, for the selected file systems.
Read/Write
I/O Size Average size of file system I/O requests, in KB, for the selected file systems or file systems. Calculated as a weighted average, which gives more weight to the file systems with the highest number of I/O requests.
Storage Processor Read/Write
IOPS Total number of file system I/O requests, in I/O per second, for the selected file system or file systems.
Storage Processor Read/Write
Unisphere performance metrics
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vVol datastore performance metrics
Metric name Description Additional breakdown categories
Bandwidth Total amount of vVol I/O requests, in KB/s, for the selected vVols.
Storage Processor
Read/Write
IOPS Total amount of vVol I/O requests, in I/O per second, for the selected vVols.
Storage Processor
Read/Write
Response Time Average time spent completing vVol I/O requests, in microseconds, for the selected vVols in the storage system. Calculated as a weighted average, which gives more weight to the vVols with the highest number of I/O requests.
Storage Processor
Fibre Channel port performance metrics
Metric name Description Additional breakdown categories
Bandwidth Total amount of Fibre Channel I/O requests, in KB/s, for the selected Storage Processors and associated Fibre Channel ports.
Read/Write
Replication Bandwidth Total number of Fibre Channel I/O replication requests, in KB/s per second, for the selected Storage Processors and associated Fibre Channel ports.
Read/Write
IOPS Total number of Fibre Channel I/O requests, in I/O per second, for the selected Storage Processors and associated Fibre Channel ports.
Read/Write
Replication IOPS Total number of Fibre Channel I/O replication requests, in I/O per second, for the selected Storage Processors and associated Fibre Channel ports.
Read/Write
Total Link Errors Total number of link errors, in I/O per second, for the selected Storage Processors and associated Fibre Channel (FC) ports.
iSCSI interface performance metrics
Metric name Description Additional breakdown categories
Bandwidth Total amount of iSCSI I/O requests, in KB/s, for the selected iSCSI interfaces.
Read/Write
IOPS Total number of iSCSI I/O requests, in I/O per second, for the selected iSCSI interfaces.
Read/Write
Unisphere performance metrics
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Ethernet port performance metrics
Metric name Description Additional breakdown categories
Bandwidth Total amount of Ethernet I/O requests, in KB/s, for the selected Storage Processors and associated Ethernet ports.
Read/Write
Packets Total amount of Ethernet I/O requests, in I/O per second, for the selected Storage Processors and associated Ethernet ports.
Read/Write
Drive performance metrics
Metric name Description Additional breakdown categories
Bandwidth Total amount of drive I/O requests, in KB/s, for the selected drives used in provisioned storage.
Storage Processor Read/Write
IOPS Total number of drive I/O requests, in I/O per second, for the selected drives used in provisioned storage.
Storage Processor Read/Write
Queue Length Average number of drive I/O requests in the system queue, in counts per second, for the selected drives used in provisioned storage. Calculated as a weighted average, which gives more weight to the drives with the highest number of I/O requests.
Storage Processor
Response Time Average time spent completing drive I/O requests, in microseconds, for the selected drives used in provisioned storage, including time spent in the queue. Calculated as a weighted average, which gives more weight to the drives with the highest number of I/O requests.
Storage Processor
Service Time Average time spent completing drive I/O requests, in microseconds, for the selected drives used in provisioned storage, not including time spent in the queue. Calculated as a weighted average, which gives more weight to the drives with the highest number of I/O requests.
Storage Processor
Tenant performance metrics
Metric name Description Additional breakdown categories
Bandwidth Total amount of I/O requests, in KB/s, for the selected tenant.
Read/Write
Unisphere performance metrics
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A.2 Real-time performance metrics
System-cache performance metrics
Metric name Description
Cache Dirty Size Amount of data in the write cache, in MB, that has not yet been flushed out to disks.
Cache Read Hit IOPS Read I/O served by Cache.
Cache Read Miss IOPS Read I/O not served by Cache.
Cache Write Hit IOPS Write I/O served by Cache, in I/O per second, that does not demand a new allocation of cache memory.
Cache Write Miss IOPS Write I/O served by Cache, in I/O per second, that demands a new allocation of cache memory.
System-resources performance metrics
Metric name Description
CPU Utilization Total amount of processing cycles, as a percentage, across all cores in the storage system SPs.
System-I/O performance metrics
Metric name Description
CIFS Bandwidth Read, Write, or Total
Amount of SMB read, write, or total I/O requests, in KB/s, for all LUNs in the storage system.
CIFS I/O Size Read, Write, or Total
Average size of SMB read or write I/O requests, in microseconds, for all LUNs in the storage system.
CIFS IOPS Read Write or Total
Number of SMB read, write, or total I/O requests, in I/O per second, for the selected LUNs.
CIFS Response Time Read or Write
Average time spent completing CIFS (SMB) read or write I/O requests, in microseconds, for all file systems in the storage system.
CIFS Response Time (Total)
Average time spent completing all CIFS (SMB) I/O requests, in microseconds, for all file systems in the storage system.
NFS Response Time Read or Write
Average time spent completing NFS read or write I/O requests, in microseconds, for all file systems in the storage system.
NFS Response Time (Total)
Average time spent completing all NFS I/O requests, in microseconds, for all file systems in the storage system.
Unisphere performance metrics
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LUN performance metrics
Metric name Description
Bandwidth Read, Write, or Total
Amount of LUN read, write, or total I/O requests, in KB/s, for the selected LUNs.
I/O Size Read or Write Average size of LUN read or write I/O requests, in KB, across all LUNs in the storage system. Calculated as a weighted average, which gives more weight to the LUNs with the highest number of I/O requests.
IOPS Read, Write, or Total
Number of LUN read, write, or total I/O requests, in I/O per second, for the selected LUNs.
Queue Length Average number of LUN I/O requests in the system queue, in counts per second, for the selected LUNs.
Response Time Average time spent completing LUN I/O requests, in microseconds, for the selected LUNs in the storage system. Calculated as a weighted average, which gives more weight to the LUNs with the highest number of I/O requests.
File system performance metrics
Metric name Description
Bandwidth Read or Write Amount of file system read or write I/O requests, in KB/s, for the selected file systems.
I/O Size Read or Write Average size of file system read or write I/O requests, in KB, across all file systems in the storage system. Calculated as a weighted average, which gives more weight to the file systems with the highest number of I/O requests.
IOPS Read or Write Number of file system read or write I/O requests, in I/O per second, for the selected file systems.
Fibre Channel port performance metrics
Metric name Description
Bandwidth Read or Write Amount of Fibre Channel read or write I/O requests, in KB/s, for the selected Storage Processors and associated Fibre Channel ports.
Requests/Second Read or Write
Number of Fibre Channel read or write I/O requests, in I/O per second, for the selected Storage Processors and associated Fibre Channel ports.
Unisphere performance metrics
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iSCSI interface performance metrics
Metric name Description
Bandwidth Read or Write Amount of iSCSI read or write I/O requests, in KB/s, for the selected iSCSI interfaces.
Requests/Second Read or Write
Number of iSCSI read or write I/O requests, in I/O per second, for the selected iSCSI interfaces.
Ethernet port performance metrics
Metric name Description
Bandwidth Read or Write Amount of iSCSI read or write I/O requests, in KB/s, for the selected iSCSI interfaces.
Packets Read or Write Number of Ethernet read or write packets per second, for the selected Storage Processors and associated Ethernet ports.
Table 1.
Drive performance metrics
Metric name Description
Bandwidth Read or Write Amount of drive read or write I/O requests, in KB/s, for the selected drives used in provisioned storage.
IOPS Read, Write, or Total
Number of drive read, write, or total I/O requests, in I/O per second, for the selected drives used in provisioned storage.
Queue Length Average number of drive I/O requests in the system queue, in counts per second, for the selected drives used in provisioned storage. Calculated as a weighted average, which gives more weight to the drives with the highest number of I/O requests.
Response Time Average time spent completing drive I/O requests, in microseconds, for the selected drives used in provisioned storage, including time spent in the queue. Calculated as a weighted average, which gives more weight to the drives with the highest number of I/O requests.
Service Time Average time spent completing drive I/O requests, in microseconds, for the selected drives used in provisioned storage, not including time spent in the queue. Calculated as a weighted average, which gives more weight to the drives with the highest number of I/O requests.
Unisphere performance metrics
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Tenant performance metrics
Metric name Description
Bandwidth Read or Write Amount of read or write I/O requests, in KB/s, for the selected tenants in the storage system.
Technical support and resources
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B Technical support and resources
Dell.com/support is focused on meeting customer needs with proven services and support.
Storage technical documents and videos provide expertise that helps to ensure customer success on Dell
EMC storage platforms.
B.1 Related resources
• CLI Guide
• Unisphere Command Line Interface User Guide
• REST API Guides
• Unisphere Management REST API Programmer’s Guide
• Unisphere Management REST API Reference Guide
• Best Practices Guide
• Dell EMC Unity: Best Practices Guide
• Additional Documentation
• Dell EMC Online Support
• Dell EMC Unity Info Hub (http://bit.ly/unityinfohub)